I believe the "closed" meetings are the sharing meetings and the "open" meetings the speaker meeting.
At the beginning of the meeting it was always mentioned by the chair that the meeting was a closed meeting and therefore only for those who are an alcoholic or think they may be. Best friends, spouses etc. were asked to leave, much less share. I was at one meeting where a best friend had come to the meeting for support and when she introduced herself as a support to her friend, she was politely asked to wait outside until the meeting was over.
They are 'anonymous' and members of AA are not comfortable sharing with those who are not alcoholics. It is supposed to be a safe place for alcoholics.
I'm sorry you felt hurt but it wasn't personal, just the rules of AA.